Same entry, according to Adler, in the Ambrosian Lexicon -- and generated (as she notes) by Josephus, Jewish War 5.474, where this headword appears (spelled with i, not ei: agiras) and is given precisely this gloss. (Perhaps a nomen agentis from a)gei/rw in the sense of "collect alms, beg"? Or perhaps a non-Greek word?)